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arXiv · 2406.04059

First-order and Berezinskii-Kosterlitz-Thouless phase transitions in two-dimensional generalized XY models

P. A. da Silva·R. J. Campos-Lopes·A. R. Pereira
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Abstract

The aim of this paper is to illustrate that generalized two-dimensional XY models (proposed by Romano and Zagrebnov) may also support a first-order phase transition. Two approaches are employed to accurately determine the critical parameter $q$ at which such a transition takes place. Furthermore, we show that the model is characterized by three distinct regions concerning both first-order and Berezinskii-Kosterlitz-Thouless phase transitions. Finally, the underlying mechanisms governing such transitions are presented, along with an estimation of the critical temperatures.

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P. A. da Silva, R. J. Campos-Lopes, A. R. Pereira. 2024-06-06. First-order and Berezinskii-Kosterlitz-Thouless phase transitions in two-dimensional generalized XY models. https://arxiv.org/abs/2406.04059

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